The specific aim of the proposed research is to conduct a systematic examination of the development of children and adults' spatial knowledge of large environments outside the school and laboratory settings. The research consists of a series of studies examining children and adults' cognitive maps of their neighborhoods, how children and adults find their way around in their neighborhoods, and how they develop cognitive maps and find their way around unfamiliar large environments. In the most comprehensive of these studies (Experiment 1) children and adults' cognitive maps of their neighborhood will be assessed in the context of a combined longitudinal/cross-sectional design spanning a three year period. Experiments 2 and 3 will examine children's memory for route and location information after they encounter a large, unfamiliar environment (the St. Louis Zoo). Experiment 3 has the added advantage of examining memory for spatial information over a long time period (8 months). In Experiment 4 subjects will be asked to recall route and location information after encountering an area as a passenger in a car while Experiment 5 will examine the extent to which subjects' cognitive maps are distorted by walking along curved roads relative to straight roads in large environments. In Experiment 6 subjects will be asked to recall spatial information that is up to 10 miles away from their homes while in Experiment 7 the effects of barriers (walls, hills, etc.) between two locations on subjects' estimates of the distances between those locations will be assessed. Finally, Experiment 8 will be conducted to gather significant descriptive information about how children and young adults find their way and locate place in large environments. The long-term goal of this research is to provide a wealth of information that can be used to advance a general theory of spatial cognition development. Achievement of this goal will provide a great deal of data about the spatial learning process in very large environments and set the norms of spatial behavior development in these settings. These norms, in turn, can be used to help in the assessment of children and adults who may have spatial information processing deficits.